Replaced _detail::CountOrEnd with rangeIsForwardOrSized and UDist

auxi/impl_algo.h

@@ -7,7 +7,7 @@
 
 
 #include "contiguous_iterator_to_ptr.h"
-#include "range_traits.h"
+#include "../util.h"  // for as_unsigned
 
 #include <cstring>
 
@@ -128,26 +128,28 @@ namespace oel::_detail
 
 
 
-	// If r is sized or multi-pass, returns element count as size_t, else end(r)
 	template< typename Range, typename... None >
-	inline auto CountOrEnd(Range & r, None...)
+	auto UDist(Range & r, None...)
 	{
-		if constexpr (iter_is_forward< iterator_t<Range> >)
+		using I = decltype(begin(r));
+		if constexpr (iter_is_forward<I>)
 		{
-			size_t n{};
-			auto it = begin(r);
+			auto    it = begin(r);
 			auto const l = end(r);
+			std::make_unsigned_t< iter_difference_t<I> > n{};
 			while (it != l) { ++it; ++n; }
 
 			return n;
 		}
-		else
-		{	return end(r);
-		}
 	}
 
 	template< typename Range >
-	auto CountOrEnd(Range & r)
-	->	decltype( static_cast<size_t>(_detail::Size(r)) )
-	{	return    static_cast<size_t>(_detail::Size(r)); }
+	auto UDist(Range & r)
+	->	decltype( as_unsigned(_detail::Size(r)) )
+	{	return    as_unsigned(_detail::Size(r)); }
+
+
+	template< typename Range >
+	inline constexpr auto rangeIsForwardOrSized =
+		!std::is_same_v< decltype( _detail::UDist(std::declval<Range &>()) ), void >;
 }

auxi/range_algo_detail.h

@@ -7,7 +7,6 @@
 
 
 #include "impl_algo.h"
-#include "../util.h" // for as_unsigned
 
 #include <algorithm>
 

dynarray.h

@@ -128,8 +128,7 @@ class dynarray
 	*
 	* Any elements held before the call are either assigned to or destroyed. */
 	template< typename InputRange >
-	auto assign(InputRange && source)
-	->	borrowed_iterator_t<InputRange>   { return _doAssign(adl_begin(source), _detail::CountOrEnd(source)); }
+	auto assign(InputRange && source) -> borrowed_iterator_t<InputRange>;
 
 	void assign(size_type count, const T & val)   { clear();  append(count, val); }
 
@@ -141,8 +140,8 @@ class dynarray
 	*
 	* Unlike std::vector, `end(source)` is not needed if `source.size()` is valid. */
 	template< typename InputRange >
-	auto append(InputRange && source)
-	->	borrowed_iterator_t<InputRange>   { return _doAppend(adl_begin(source), _detail::CountOrEnd(source)); }
+	auto append(InputRange && source) -> borrowed_iterator_t<InputRange>;
+
 	//! Equivalent to `std::vector::insert(end(), il)`
 	void append(std::initializer_list<T> il)   { append<>(il); }
 	/**
@@ -340,7 +339,6 @@ class dynarray
 		_m.reservEnd = _m.data + capToCheck;
 	}
 
-
 	void _moveInternBase(_internBase & src) noexcept
 	{
 		_internBase & dest = _m;
@@ -430,6 +428,17 @@ class dynarray
 	}
 
 
+	template< typename InputRange >
+	auto _emplBackRange(InputRange & src)
+	{
+		auto it = adl_begin(src);
+		auto l  = adl_end(src);
+		for (; it != l; ++it)
+			emplace_back(*it);
+
+		return it;
+	}
+
 	template< typename InputIter >
 	InputIter _doAssign(InputIter src, size_type const count)
 	{
@@ -490,33 +499,6 @@ class dynarray
 		}
 	}
 
-	template< typename InputIter, typename Sentinel >
-	InputIter _doAssign(InputIter first, Sentinel const last)
-	{	// single-pass iterator and unknown count
-		clear();
-		for (; first != last; ++first)
-			emplace_back(*first);
-
-		return first;
-	}
-
-	template< typename InputIter, typename Sentinel >
-	InputIter _doAppend(InputIter first, Sentinel const last)
-	{	// single-pass iterator and unknown count
-		auto const oldSize = size();
-		OEL_TRY_
-		{
-			for (; first != last; ++first)
-				emplace_back(*first);
-		}
-		OEL_CATCH_ALL
-		{
-			erase_to_end(begin() + oldSize);
-			OEL_RETHROW;
-		}
-		return first;
-	}
-
 	template< typename InputIter >
 	InputIter _doAppend(InputIter src, size_type const count)
 	{
@@ -635,11 +617,11 @@ typename dynarray<T, Alloc>::iterator
 	OEL_DYNARR_INSERT_STEP1
 #undef OEL_DYNARR_INSERT_STEP1
 
-	auto first = adl_begin(src);
-	auto const count = _detail::CountOrEnd(src);
+	static_assert( _detail::rangeIsForwardOrSized<Range>,
+		"insert_range requires that source models std::ranges::forward_range or that source.size() is valid" );
 
-	static_assert( std::is_same_v<decltype(count), size_t const>,
-			"insert_range requires that source models std::ranges::forward_range or that source.size() is valid" );
+	auto       first = adl_begin(src);
+	auto const count = _detail::UDist(src);
 
 	size_t const bytesAfterPos{sizeof(T) * (_m.end - pPos)};
 	T * dLast;
@@ -723,6 +705,66 @@ inline void dynarray<T, Alloc>::append(size_type count, const T & val)
 	_m.end += count;
 }
 
+template< typename T, typename Alloc >
+template< typename InputRange >
+inline auto dynarray<T, Alloc>::append(InputRange && source)
+->	borrowed_iterator_t<InputRange>
+{
+	if constexpr (_detail::rangeIsForwardOrSized<InputRange>)
+	{
+		return _doAppend(adl_begin(source), _detail::UDist(source));
+	}
+	else
+	{	auto const oldSize = size();
+		OEL_TRY_
+		{
+			return _emplBackRange(source);
+		}
+		OEL_CATCH_ALL
+		{
+			erase_to_end(begin() + oldSize);
+			OEL_RETHROW;
+		}
+	}
+}
+
+template< typename T, typename Alloc >
+template< typename InputRange >
+inline auto dynarray<T, Alloc>::assign(InputRange && source)
+->	borrowed_iterator_t<InputRange>
+{
+	if constexpr (_detail::rangeIsForwardOrSized<InputRange>)
+	{
+		return _doAssign(adl_begin(source), _detail::UDist(source));
+	}
+	else
+	{	clear();
+		return _emplBackRange(source);
+	}
+}
+
+
+template< typename T, typename Alloc >
+dynarray<T, Alloc>::dynarray(size_type n, for_overwrite_t, Alloc a)
+ :	_m(a)
+{
+	_initReserve(n);
+	_m.end = _m.reservEnd;
+	_detail::DefaultInit<allocator_type>::call(_m.data, _m.reservEnd, _m);
+
+	(void) _debugSizeUpdater{_m};
+}
+
+template< typename T, typename Alloc >
+dynarray<T, Alloc>::dynarray(size_type n, Alloc a)
+ :	_m(a)
+{
+	_initReserve(n);
+	_m.end = _m.reservEnd;
+	_uninitFill::call(_m.data, _m.reservEnd, _m);
+
+	(void) _debugSizeUpdater{_m};
+}
 
 template< typename T, typename Alloc >
 dynarray<T, Alloc>::dynarray(dynarray && other, Alloc a)
@@ -769,28 +811,6 @@ dynarray<T, Alloc> &  dynarray<T, Alloc>::operator =(const dynarray & other) &
 	return *this;
 }
 
-template< typename T, typename Alloc >
-dynarray<T, Alloc>::dynarray(size_type n, for_overwrite_t, Alloc a)
- :	_m(a)
-{
-	_initReserve(n);
-	_m.end = _m.reservEnd;
-	_detail::DefaultInit<allocator_type>::call(_m.data, _m.reservEnd, _m);
-
-	(void) _debugSizeUpdater{_m};
-}
-
-template< typename T, typename Alloc >
-dynarray<T, Alloc>::dynarray(size_type n, Alloc a)
- :	_m(a)
-{
-	_initReserve(n);
-	_m.end = _m.reservEnd;
-	_uninitFill::call(_m.data, _m.reservEnd, _m);
-
-	(void) _debugSizeUpdater{_m};
-}
-
 template< typename T, typename Alloc >
 dynarray<T, Alloc>::~dynarray() noexcept
 {

unit_test/util_gtest.cpp

@@ -299,6 +299,8 @@ TEST(utilTest, detailCountOrEnd_disabledSize)
 	A src{1};
 	auto v = oel::view::subrange(TooSimpleIter<A::iterator>{src.begin()}, src.end());
 
-	auto n = oel::_detail::CountOrEnd(v);
+	static_assert(oel::_detail::rangeIsForwardOrSized<decltype(v)>);
+
+	auto n = oel::_detail::UDist(v);
 	EXPECT_EQ(1u, n);
 }